Synthesis and Optical Properties of Asymmetric Polyamides Derived from Optically Active Cyclic Dicarboxylic Acids

1971 ◽  
Vol 4 (6) ◽  
pp. 718-725 ◽  
Author(s):  
C. G. Overberger ◽  
Y. Shimokawa
Keyword(s):  
Optical Properties ◽  
Dicarboxylic Acids ◽  
Optically Active

On the syntheses and the optical properties of optically active 2-pyrazoline compounds

1979 ◽  
Vol 57 (3) ◽  
pp. 360-366 ◽  
Author(s):  
Makoto Mukai ◽  
Takashi Miura ◽  
Masahiro Nanbu ◽  
Toshinobu Yoneda ◽  
Yohji Shindo
Keyword(s):  
Optical Properties ◽  
Optical Activity ◽  
Optically Active ◽  
Spectroscopic Techniques ◽  
Considerable Influence ◽  
Pyrazoline Ring

Optically active 2-pyrazolines were synthesized and their optical properties were studied using various spectroscopic techniques to investigate the effects of substituents at the 3 and 5 positions of the 2-pyrazoline ring on their optical activity. It was found that in the case of 5-substituted-1,3-diphenyl-2-pyrazoline derivatives, the substituent at the 5 position has considerable influence on the optical activity, whereas in 3-substituted-1,5-diphenyl-2-pyrazoline derivatives, the substituent at the 3 position has no such influence.

ChemInform Abstract: ON THE SYNTHESES AND THE OPTICAL PROPERTIES OF OPTICALLY ACTIVE 2-PYRAZOLINE COMPOUNDS

1979 ◽  
Vol 10 (24) ◽  
Author(s):  
M. MUKAI ◽  
T. MIURA ◽  
M. NANBU ◽  
T. YONEDA ◽  
Y. SHINDO
Keyword(s):  
Optical Properties ◽  
Optically Active

Optical properties of a single type of optically active center inSi∕Si:Ernanostructures

2004 ◽  
Vol 70 (11) ◽  
Author(s):  
N. Q. Vinh ◽  
H. Przybylińska ◽  
Z. F. Krasil’nik ◽  
T. Gregorkiewicz
Keyword(s):  
Optical Properties ◽  
Active Center ◽  
Optically Active ◽  
Single Type

scholarly journals Synthesis of monomers for the preparation of optically active poly(amido–imide)s. Part 1. Synthesis of chiral imides containing a fragment of the natural amino acid based on nitrophenylcycloalkanedicarboxylic acids

2019 ◽  
Vol 57 (1) ◽  
pp. 27-40
Author(s):  
Anna A. Koverda ◽  
◽  
Alexandra I. Korshunova ◽  
Mikhail N. Koverda ◽  
Evgeny N. Sechin ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Amino Acid ◽  
Membrane Separation ◽  
Chloroform Solution ◽  
Dicarboxylic Acids ◽  
Optically Active ◽  
Alkylation Reaction ◽  
Catalytic Systems ◽  
Amino Acid Fragment ◽  
Acid Fragment

Previously it was shown that the stereochemical result of the alkylation reaction of benzene with cycloalkanedicarboxylic acids depends on the order of mixing the reagents. The resulting diastereomerically pure derivatives can be used as precursors of monomers for the synthesis of optically active poly(amido–imide)s, which are basic materials in chiral chromatographic separation. Their potential for use in chiral catalytic systems, liquid crystals in ferroelectric and nonlinear optics, in the manufacture of electrodes for enantioselective recognition during bioelectrosynthesis, membrane separation technology, etc. is shown. Nitration reactions of alkyl derivatives were carried out with their subsequent imidization with natural amino acids. The resulting diastereomerically pure dicarboxylic acids are nitrated with low selectivity, unlike their anhydrides, so the nitro derivatives were synthesized by nitrating the anhydrides with anhydrous nitric acid in chloroform solution. The racemization of the α-carbon center of the amino acid fragment occurs during the imidization reaction in glacial acetic acid. Using of DMF as a solvent under mild conditions is preferable, as it eliminates the possibility of racemization of the chiral center of the amino acid fragment. It was also found that during the preparation of imides, the configuration of the chiral centers of the cycloalkane dicarboxylic acid fragment is preserved. Nitrophenylnorbornanedicarboxylic acid forms an anhydride directly during synthesis in acetic acid, unlike cyclohexanedicarboxylic acids, due to its spatial structure. Nitrophenylnorbornanedicarboxylic acid is also characterized by easier imidization. The structure was determined using 1H, 13C NMR, 1H-1H NOESY, 1H-1H COSY, HPLC, capillary electrophoresis.

scholarly journals Influence of organic aerosol composition determined by offline FIGAERO-CIMS on particle absorptive properties in autumn Beijing

2021 ◽  
Author(s):  
Jing Cai ◽  
Cheng Wu ◽  
Jiandong Wang ◽  
Wei Du ◽  
Feixue Zheng ◽  
...  
Keyword(s):  
Optical Properties ◽  
Urban Environment ◽  
Light Absorption ◽  
Radiative Forcing ◽  
Dicarboxylic Acids ◽  
Organic Aerosol ◽  
Molecular Composition ◽  
Absorption Enhancement ◽  
Ionization Mass ◽  
Aerosol Composition

Abstract. Organic aerosol (OA) is a major component of fine particulate matter (PM) affecting air quality, human health, and the climate. The absorptive and reflective behavior of OA components contributes to determining particle optical properties and thus their effects on the radiative budget of the troposphere. There is limited knowledge on the influence of the molecular composition of OA on particle optical properties in the polluted urban environment. In this study, we characterized the molecular composition of oxygenated OA collected on filter samples in autumn of 2018 in Beijing, China, with a filter inlet for gases and aerosols coupled to a high-resolution time-of-flight chemical ionization mass spectrometer (FIGAERO-CIMS). Three haze episodes occurred during our sampling period with daily maximum concentrations of OA of 50, 30, and 55 µg m−3, respectively. We found that the signal intensities of dicarboxylic acids and sulfur-containing compounds increased during the two more intense haze episodes, while the relative contributions of wood-burning markers and other aromatic compounds were enhanced during the cleaner periods. We further assessed the optical properties of oxygenated OA components by combining the detailed chemical composition measurements with collocated particle light absorption measurements. We show that light-absorption enhancement (Eabs) of black carbon (BC) was mostly related to more oxygenated OA (e.g. dicarboxylic acids), likely formed in aqueous-phase reactions during the intense haze periods with higher relative humidity, and speculate that they might contribute to lensing effects. Aromatics and nitro-aromatics (e.g. nitrocatechol and its derivatives) were mostly related to a high light absorption coefficient (babs) consistent with light-absorbing (brown) carbon (BrC). Our results provide information on oxygenated OA components at the molecular level associated with BrC and BC particle light-absorption and can serve as a basis for further studies on the effects of anthropogenic OA on radiative forcing in the urban environment.

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